An RFID tag includes a sensor for determining a transient state or condition of a product to which the tag is associated, and a display. The tag may be passive, semi-passive, or active. In response to receipt at the tag of a read signal that includes a first value associated with the transient state or condition, a comparison is performed. The comparison compares the first value, with a second value generated by the sensor in response to receipt of the read signal. As a result of the comparison, an indication is provided on the display. The information displayed is a function of the comparison. In one embodiment, the display provides different color indications depending on the transient state or condition sensed.